根际细菌群落结构对黄瓜幼苗干旱胁迫的响应  

Response of rhizosphere bacterial community structure to drought stress in cucumber seedlings

作　　者：王灿 赵文麟 张新梅 许彬[3] 罗文 解志强 张应华[1] 许俊强[1,3] WANG Can;ZHAO Wen-lin;ZHANG Xin-mei;XU Bin;LUO Wen;XIE Zhi-qiang;ZHANG Ying-hua;XU Jun-qiang(Yunnan Agricultural University/Dian-Tai Engineering Research Center for Characteristic Agriculture Industrialization of Yunnan Prov-ince,Kunming 650201,China;Wenshan Academy of Agricultural Sciences,Wenshan,Yunnan 663000,China;Key Laboratory of Veg-etable Biology of Yunnan Province,Yunnan Agricultural University,Kunming 650201,China)

机构地区：[1]云南农业大学/云南省滇台特色农业产业化工程研究中心,昆明650201 [2]文山州农业科学院,云南文山663000 [3]云南农业大学云南省蔬菜生物学重点实验室,昆明650201

出　　处：《西南农业学报》2024年第1期92-100,共9页Southwest China Journal of Agricultural Sciences

基　　金：云南省基础研究计划(202301AT070502);云南省重大科技计划项目(202102AE090005);云南省农业联合专项(202101BD070001-115);云南省科技人才和平台计划(202205AF150017、202205AF150021)。

摘　　要：【目的】了解根际细菌群落结构和功能对黄瓜幼苗干旱胁迫的响应。【方法】采用盆栽控水法设置干旱处理D和正常处理N,利用Illumina NovaSeq测序技术测定黄瓜幼苗根际细菌群落结构和多样性。【结果】处理N的叶绿素和可溶性糖含量分别是2.440和10.380 mg/g,显著高于处理D的1.547和8.356 mg/g;处理D的脯氨酸和丙二醛含量分别为51.807μg/g和54.848 nmol/g,显著高于处理N的32.628μg/g和29.005 nmol/g;处理N的根系活力为32.670μg/(g·h),显著高于处理D的20.714μg/(g·h);处理N的SOD含量为324.826 U/g,显著低于处理D的578.363 U/g;黄瓜幼苗根际细菌群落中,门分类水平下丰度前5位的是变形菌门(Proteobacteria)、芽单胞菌门(Gemmatimonadota)、拟杆菌门(Bacteroidota)、酸杆菌门(Acidobacteria)和放线菌门(Ac⁃tinobacteriota);α多样性指数(Chao1、Shannon、Simpson)中各处理间无显著差异,但PCoA分析显示,两处理间细菌群落结构差异显著;处理N与处理D相比,芽单胞菌显著升高,而拟杆菌和厚壁菌则显著下降;LEfSe结果显示,处理D显著富集以拟杆菌门和厚壁菌门为主的Muribaculaceae、梭菌纲(Clostridia)、芽孢杆菌纲(Bacilli)等有益细菌;根际细菌群落功能分析发现,处理D显著增加RNA加工和修饰、染色质结构和动力学、转录、氨基酸运输和代谢、碳水化合物的运输和代谢等相关功能的丰度,并上调与硫胺素等次级代谢物相关的合成途径及以糖类、氨基酸为主的降解代谢途径。【结论】干旱胁迫对黄瓜幼苗根际细菌群落结构有显著影响,促进根际土壤中以拟杆菌和厚壁菌为主的有益微生物显著富集,并对其细菌群落生命活动产生诱导和促进作用,使与硫胺素等次级代谢物相关的合成途径和以糖类、氨基酸为主的降解代谢途径丰度显著上调。以期为挖掘在干旱胁迫下对黄瓜秧苗生长可能有正向作用的土壤有益菌互作机制研究提供新思路【Objective】The study aimed to understand the response of rhizosphere bacterial community structure and function to drought stress in cucumber seedlings.【Method】Potted water control method was used to set up drought treatment D and normal treatment N,and the rhizo⁃sphere bacteria community structure and diversity in cucumber seedlings were determined by Illumina NovaSeq sequencing.【Result】The contents of chlorophyll and soluble sugar in treatment(N)were 2.440 and 10.380 mg/g,respectively,which were significantly higher than that of drought treatment(D),which was 1.547 and 8.356 mg/g(P<0.05).The contents of proline and malondialdehyde in treatment D was 51.807μg/g and 54.848 mol/g,respectively,which were significantly higher than those of treatment N(32.628μg/g and 29.005 mol/g).The root activity of treatment N was 32.670μg/(g·h),which was significantly higher than that of treatment D with 20.714μg/(g·h).Superoxide dismutase(SOD)content of treatment N was 324.826 U/g,which was significantly lower than that of treatment D with 578.363 U/g.In the rhizosphere bacterial community of cucumber seedlings,the top five in abundance at the taxonomic level were Pro⁃teobacteria,Gemmatimonadota,Bacteroidota,Acidobacteriota and Actinobacteriota.There was no significant difference among treatments inαdiversity index(Chao1,Shannon,Simpson).But PCoA analysis showed that there was significant difference in bacterial community struc⁃ture between the two treatments.Comparing to treatment D,Gemmatimonadota of treatment N was obviously up⁃regulated,while Bacteroidota and Firmicutes were obviously down⁃regulated(P<0.05).LEfSe results showed that beneficial bacteria such as Muribaculaceae,Clostridia,Bacilli,etc.,which mainly belonging to Bacteroidota and Firmicutes,were significantly enriched in treatment D.The functional analysis of rhizosphere bacterial community showed that the abundance of RNA processing and modification,chromatin structure and dynamics,tran⁃scription,amino acid transport and metabolism,

关 键 词：黄瓜 幼苗 干旱胁迫 根际细菌 群落结构 

分 类 号：S642[农业科学—蔬菜学]